• NASA detected an asteroid approaching Earth
  • The asteroid follows an Earth-crossing orbit
  • 2020 KE4 is big enough to produce a powerful mid-air explosion

An asteroid almost as big as a building is expected to approach Earth on Wednesday (June 3). According to NASA’s Center for Near-Earth Object Studies (CNEOS), the incoming asteroid will cross the planet’s path during its upcoming visit.

The approaching asteroid has been identified by NASA’s asteroid tracker as 2020 KE4. As indicated in CNEOS’ database, this asteroid has an estimated diameter of about 171 feet, making it almost as tall as the Leaning Tower of Pisa in Italy.

According to CNEOS, the asteroid is currently headed for Earth at a speed of over 20,000 miles per hour. This means the asteroid will fly past the planet at an average speed that’s faster than the orbital velocity of NASA’s Space Shuttle.

2020 KE4 was first observed on May 11. According to NASA’s orbit diagram, the asteroid follows a trajectory that extends beyond the orbit of Mars. As the asteroid travels around the Sun, it occasionally intersects Earth's path. Due to its natural Earth-crossing orbit, 2020 KE4 has been classified as an Apollo asteroid.

Given 2020 KE4’s size and current speed, it most likely won’t cause an impact event on Earth if it hits the planet during one of its near-intersection flybys. Instead of hitting the ground, the asteroid will most likely burn up in the atmosphere and explode in the sky.

Depending on the size of an asteroid, the energy from its airburst could be equivalent to multiple atomic bombs. For instance, the 66-foot asteroid that exploded over Russia in 2013 produced energy of about 30 atomic bombs.

Although the atmosphere was able to absorb much of the explosion’s energy, the blast wave was still powerful enough to damage thousands of buildings and injure people on the ground.

Fortunately, CNEOS noted that 2020 KE4 is not in danger of hitting Earth during its upcoming visit. According to the agency, the asteroid will safely fly past the planet on June 3 at 2:01 a.m. EDT from a distance of 0.01966 astronomical units or about 1.8 million miles away.

The asteroid’s next near-Earth approach is not expected to happen until May 2, 2082. During this time, 2020 KE4 will zip past Earth from a distance of 0.35115 astronomical units or about 33 million miles away.